Field of the Invention
The present invention relates to a device for estimating the moving speed of a mobile body and a control device for the mobile body.
Description of the Related Art
There has been suggested a technique of moving a mobile body such as a mobile robot or the like in an operating environment space in which any other mobile body or the like exists together, for example, in Japanese Patent Application Laid-Open No. 2012-428585 (hereinafter referred to as Patent Document 1).
In the technique as described in Patent Document 1, it is necessary to estimate a future position of the mobile body. Additionally, the estimation requires an accurate estimated value or measured value of the moving speed of the mobile body.
It should be noted here that the momentary moving speed (instantaneous moving speed) of the mobile body vibrates in some cases around the average moving speed even if the moving distance (average moving speed) per unit time of the mobile body is substantially constant depending on the mode of the moving action of the mobile body.
For example, a legged mobile body such as a person or a legged mobile robot moves while repeating the landing of each leg and the movement of the leg in the air and therefore the upper body or base of the legged mobile body moves in such a way that the instantaneous moving speed in the right-left direction, the up-down direction, or the front-rear direction of the mobile body periodically vibrates.
In addition, even if this instantaneous moving speed of the mobile body is sequentially estimated or measured, the instantaneous moving speed has a speed component in a direction different from the actual moving direction of the mobile body or deviates from the average moving speed in the moving direction. Accordingly, if the future position is predicted from the estimated value or measured value of the instantaneous moving speed of the mobile body, a wrong prediction is easily made.
Incidentally, there can be an idea that the moving speed of the mobile body is estimated by performing processing of averaging the estimated values or measured values of the instantaneous moving speed of the mobile body. In this case, however, if the time width for averaging is short, the vibration components of the instantaneous moving speed cannot be sufficiently removed. Moreover, if the time width for averaging is long, the moving speed of the mobile body is estimated too late.